The apparatus of the present invention comprises a further improvement over the horizontal oscillating barrel apparatus as disclosed in U.S. Pat. No. 3,674,673 of July 4, 1972, for "Apparatus for Electroplating Workpieces", which is also assigned to the assignee of the present invention. The apparatus as disclosed in the aforementioned patent, the substance of which is incorporated herein by reference, constituted a major breakthrough in the treatment of bulk quantities of workpieces over conventional prior art type rotating treating barrels which generally were of a polygonal cross sectional configuration, such as a hexagonal configuration, for example, and further included a removable door panel for gaining access to the interior of the barrel. The improved efficiency and load-carrying capacity of horizontal oscillating type treating barrels of the type to which the present invention is directed has occasioned a widespread commercial acceptance thereof in view of the economies provided and their increased adaptation to automatic processing of bulk quantities of small workpieces.
In accordance with the apparatus as disclosed in the aforementioned U.S. Pat. No. 3,674,673, a control of the angular oscillation of the barrel is achieved by providing stops on one of the end members of the barrel adapted to coact with an abutment on the carrier framework, thereby restricting angular oscillation of the barrel beyond a position at which workpieces are inadvertently discharged from the elongated opening formed in the foraminous barrel wall extending between the opposite end members. The present invention provides for an improved stop arrangement for controlling the angularity of oscillation of the barrel while immersed in a liquid treating solution, as well as while the barrel is disposed in an elevated position so as to facilitate drainage of entrapped treating solution from the interior of the barrel and the workpieces therein. The improved drive and stop arrangement minimizes exposure and contact of the drive gear with the fumes and liquid solutions associated in the processing of workpieces through various chemical and electrochemical treatment steps, such as through a cleaning, electroplating and rinsing operation, thereby providing for improved control and further increasing the durability of the barrel-type treating apparatus. The present invention further provides for an improved treating barrel work carrier of the horizontal oscillating type, whereby an improvement is effected in the manner by which the barrel is supported for rotary movement from the carrier framework, eliminating torsional forces on the framework and further including a novel bearing arrangement providing for increased durability and facilitating periodic maintenance and replacement of the bearing assembly.